Father of Modern Tropical Meterology

https://www.tallahassee.com/story/news/hurricane/2018/06/04/forecasting-model-created-florida-state-critical-tool-national-hurricane-center/661956002/

With this year’s hurricane season under way, the country will be taking its cues from the National Hurricane Center in Miami, ground zero for tracking tropical disturbances.

Among the models used at the center is the Florida State University Superensemble, a breakthrough forecasting system created in 1998 by T.N. Krishnamurti, a meteorology professor who became internationally known as the “Father of Modern Tropical Meteorology.”

The FSU Superensemble quickly gained a reputation for its accuracy in predicting storm tracks. In 2000, Krishnamurti first began offering the model’s predictions to the National Hurricane Center.

With this year’s hurricane season under way, the country will be taking its cues from the National Hurricane Center in Miami, ground zero for tracking tropical disturbances.

Among the models used at the center is the Florida State University Superensemble, a breakthrough forecasting system created in 1998 by T.N. Krishnamurti, a meteorology professor who became internationally known as the “Father of Modern Tropical Meteorology.”

The FSU Superensemble quickly gained a reputation for its accuracy in predicting storm tracks. In 2000, Krishnamurti first began offering the model’s predictions to the National Hurricane Center.



T.N. Krishnamurti, who taught meteorology at FSU from 1967 to 2008, is credited with developing the FSU Superensemble weather forecasting model. He died in February 2018 at 86. (Photo: Special to the Democrat)

Krisnhamurti died in February at age 86. But his legacy is secure in the model and the work of those meteorologists he has taught and mentored.

“The development of the Superensemble Hurricane model is one of FSU’s greatest contributions to science,” said Gary Ostrander, FSU’s vice president for research. "The model developed by Professor Krisnhamurti has long been a valuable tool for meteorologists who have the difficult job in determining the paths of potentially life-threatening storms.”
Distinguished career

Tiruvalam Natarajan Krishnamurti, a native of South India, earned his bachelor’s degree in physics from Delhi University and his master’s degree in meteorology from Andhra University in Visakhapatnam, Andhra Pradesh. In 1959, he earned his Ph.D. in meteorology from the University of Chicago, where he was a student of Herbert Riehl, considered a pioneer of hurricane research.

Krishnamurti joined the faculty at Florida State in 1967, beginning a distinguished teaching and research career that continued until his retirement in 2008. He remained sought after as a professor emeritus in the Department of Earth, Ocean and Atmospheric Science at FSU, where he was the Lawton Distinguished Professor in Meteorology.

Ruby, his wife of 57 years, also is a professor emeritus in the Department of Earth, Ocean and Atmospheric Science at FSU. Her research expertise is in geophysical fluid dynamics.

Regarded as one of the world’s top meteorology scholars, Krishnamurti was awarded the International Meteorological Organization top prize in 1996 from the World Meteorological Organization. He also was recipient of the Carl Gustav-Rossby Research Medal from the American Meteorological Society.

In 2001, FSU entered a 20-year agreement with WeatherPredict Consulting, an international firm that provides data on evolving hurricane risks, weather and oceanic conditions. An FSU spokesman said details of the deal are confidential, citing a public records exemption that protects trade secrets and proprietary information of state sponsored research.

The company has made the FSU Superensemble forecasting information available to the National Hurricane Center since 2006.

“It uses a combination of weighted, bias-corrected input models to create track and intensity forecasts for hurricanes and tropical storms,” said Richard Pasch, senior hurricane specialist at the National Hurricane Center. “This differs from a simple model consensus forecast (TCON or TVCN), which uses a simple average of the input models. The FSSE has been one of the most accurate numerical guidance tools for hurricane forecasting and warning at the National Hurricane Center.”

Pasch has worked at the Hurricane Center for 30 years. He earned his Ph.D. in meteorology under Krishnamurti in 1983.

“It is one of our primary tools,” he said of the FSSE model. “It tends to be about the most accurate."

Pasch, who spoke at Krishnamurti’s memorial, said his mentor remained active in research up until his death.

“WeatherPredict maintains the model, but it has its roots in Professor Krishnamurti’s lab,” he said.

Vasu Misra, an associate professor of meteorology at FSU, earned his master’s and Ph.D while studying under Krishnamurti from 1992 to 1997.

He describes his mentor as “legend in tropical meteorology,” who conducted research on monsoons and tropical cyclones around the world.

How the Superensemble works

Mark Bourassa, associate director for the Center for Ocean-Atmospheric Prediction Studies and a meteorology professor at FSU, said the FSU invention is a combination or "ensemble" of other weather forecast models. Each of these models use knowledge of physical laws and the weather at the start of the forecast to estimate the weather in the future.

“NOAA routinely produces a simple average of such models,” he said. “The FSU Superensemble does more than that. It uses knowledge of model shortcomings, based on

the proceeding weeks of forecasts, to adjust each of these forecasts before they are averaged. These corrections and the resulting improvement in the forecasts are what puts the 'super' in superensemble.“

Misra said the FSU Superensemble became known under Krishnamurti because of its success in forecasting the track and intensity of Atlantic hurricanes. In addition, he said, the model has outperformed other weather models in forecasting rainfall in the tropics and in forecasting climate a season in advance.

The uniqueness of the FSU Superensemble, said Misra, is in the weight given to each of the individual model forecasts entered into the superensemble. These weights are determined by statistical techniques on the performance of the individual model forecasts relative to the observations for past weather events.

“Superensemble uses a combination of forecast models,” he said. “It has usually shown itself to be superior to the best individual forecast model, which makes it quite unique. It is able to correct for systematic errors in the models and compensate for bad with good models through its weighted average technique.”
Remembering a giant in the field

Misra said Krishnamurti was driven by new discoveries in understanding and improving weather and seasonal climate forecast skills in the tropics. That drive attracted graduate students and scholars from all over the world.

“He was one of the foremost developers and users of numerical weather and climate models for several decades,” he said. “He had the prescient wisdom to pursue numerical modeling from early on in his career, which he believed was the future of the field.”

Eric Williford, a WeatherPredict consulting manager of the operational weather forecasting team, said Krishnamurti's legacy will lively on through his research, students and academic colleagues.

“Dr. Krishnamurti was a giant in the fields of Tropical Meteorology and Numerical Weather Forecasting for nearly 60 years.... We greatly miss his expertise, his scientific discussions, and the friendship that he had with several of us.”